Direct temporal characterization of sub-3-fs deep UV pulses generated by resonant dispersive wave emission.

We report on the complete temporal characterization of ultrashort pulses, generated by resonant dispersive wave emission in gas-filled hollow-capillary fibers, with energy in the microjoule range and continuously tunable from the deep-ultraviolet to the ultraviolet. Temporal characterization of such ultrabroad pulses, particularly challenging in this spectral region, was performed using an all-in-vacuum setup for self-diffraction frequency resolved optical gating (SD-FROG). Sub-3-fs pulses were measured, tunable from 250 nm to 350 nm, with a minimum pulse duration of 2.4 ± 0.1 fs.

A flexible beamline combining XUV attosecond pulses with few-femtosecond UV and near-infrared pulses for time-resolved experiments.

We describe a beamline where few-femtosecond ultraviolet (UV) pulses are generated and synchronized to few-cycle near-infrared (NIR) and extreme ultraviolet (XUV) attosecond pulses. The UV light is obtained via third-harmonic generation in argon or neon gas when focusing a phase-stabilized NIR driving field inside a glass cell that was designed to support high pressures for enhanced conversion efficiency. A recirculation system allows reducing the large gas consumption required for the nonlinear process. Isolated attosecond pulses are generated using the polarization gating technique, and the photon spectrometer employed to characterize the XUV radiation consists of a new design based on the combination of a spherical varied-line-space grating and a cylindrical mirror. This design allows for compactness while providing a long entrance arm for integrating different experimental chambers. The entire interferometer is built under vacuum to prevent both absorption of the XUV light and dispersion of the UV pulses, and it is actively stabilized to ensure an attosecond delay stability during experiments. This table-top source has been realized with the aim of investigating UV-induced electron dynamics in neutral states of bio-relevant molecules, but it also offers the possibility to implement a manifold of novel time-resolved experiments based on photo-ionization/excitation of gaseous and liquid targets by ultraviolet radiation. UV pump-XUV probe measurements in ethyl-iodide showcase the capabilities of the attosecond beamline.

[Notification of family history of diabetes]. / El antecedente familiar de diabetes como dato referido.

In clinical practice the presence of a positive family history of diabetes mellitus is one of the criteria to perform a glucose screening test. However it has been shown not to be always reliable. The aim of this study is to verify the concordance between the data referred by a group of daughters about the existence of diabetes mellitus in both parents, the data given by their parents, and a corroboration by blood glucose testing of the parents. A total of 82 triads (father, mother and daughter) were studied. The daughters were healthy and belonged to a cohort of perinatal studies of the Instituto Nacional de Perinatologia in Mexico City; they were not pregnant and had both patients alive, who agreed to participate in the study. Each daughter was asked about her parents history of diabetes having three options as an answer: yes, no, do not know. The same information about themselves was asked to the parents separately, not giving a chance to the members of the triad to communicate among themselves. The necessary glucose tests were performed to integrate a diagnosis by accepted international criteria. A chi-square test was used to compare the data referred by parents and daughters; agreement percentage (kappa values) were calculated. A prespecified order test was performed to the answers given and evaluated by occurrence rates (Bartholomew's test). In the latter analysis there were significant differences (p < 0.001) between the answer given by the parents, daughter and the confirmed blood glucose values. No differences were found between what the parents said, nor in what they said and what the daughters answered.

[Evaluation of a breakfast as screening test for the detection of gestational diabetes]. / Evaluación de un desayuno como prueba de tamiz para la detección de diabetes gestacional.

A standard breakfast was evaluated as a screening test (BT) for gestational diabetes in a case-control study. The breakfast had a high carbohydrate content and was designed based on women's preferences in a similar sample. Women were selected with a standard 50 g, 1 hour glucose screening test (GT). Fifteen women had a positive GT and 15 had a negative test. A glucose tolerance test (GTT) and a standard breakfast (719 kcal) were performed to all women. Age, weight, height, tricipital and subscapular skinfold thicknesses were obtained by previously standardized personnel and glucose levels were determined by an automatic technique (oxidase glucose). Ten women had gestational diabetes. Sensitivity and specificity were calculated for the GT and several values of the BT, in order to identify the threshold and optimum time. Concordance of both screening tests with GTT was calculated through Kappa test. For the BT, a sensitivity of 0.90 and specificity of 1.00 with a glucose level > or = 140 mg/L (7.2 mmol/L) at 60 and 90 minutes were found. The 60 minutes timing were preferred due to a shorter waiting time to performed the test. Concordance of GTT with GT and BT was 0.53 and 0.92 respectively, both statistically significant. GT had high frequency of false negative values (6/15) that explain the low kappa value. Standard breakfast can be used as an alternative method for assessing carbohydrate tolerance in pregnancy with a better physiological response in these women.

El efecto diabetogénico del embarazo, ¿afecta a todas las gestantes? / The diabetogenic effect in pregnancy, Does it effect all pregnancy women?

Es el objetivo de este trabajo el comportamiento de los valores de glucosa durante la segunda mitad del embarazo en un grupo de gestantes sin patología evidente, que no desarrollaran diabetes gestacional y que se dividen para su análisis de acuerdo a indicadores de riesgo. Se evaluaron 29 mujeres en 4 ocasiones, 3 durante la gestación (semana 23, 30 y 36 + - 7 días) y 1 en el post-parto (50 + - 14 días). Se dividió a la población en: alto riesgo (AR) a mujeres que presentaron antecedentes familiares de diabetes mellitus en padre y/o madre positivos, y/o porcentaje de peso para la talla pregestacional (%P/T pregest.) igual o mayor a 127; mientras que se asignó bajo riesgo (BR) a las mujeres con ausencia de los indicadores antes mencionados y cuya edad fuera menor a los 31 años y el número de gestaciones menos abortos menor a 4. Se determinó glucosa en suero mediante glucosa oxidasa tanto al ayuno como en el post-prandio de 2 hrs., después de la ingesta de una carga de 100 g de glucosa. La compración entre ambos grupos de riesgo se evaluó con estadística paramétrica. El comportamiento del ayuno en ambos grupos no presenta diferentes de BR se observa a las 2 hrs., un comportamiento igualmente uniforme con una mínima variabilidad hasta el post-parto. Situación que no se presenta con las mujeres de AR cuyos valores de glucosa son significativamente mayores que los del BR y además se incrementan conforme la gestación avanza hasta en un 34%, obteniéndose una diferencia significativa entre las semanas 30 a 36 (p menor a 0.05). De los indicadores de riesgo, el % P/T pregest y la edad, fueron los indicadores con mayor grado de asociación con altos valores de glucosa.

Hyperinsulinaemia and normal glucose tolerance tests in pregnancy

Hyperinsulinaemia is a condition present during late pregnancy, returning to normal after delivery. Since some pregnant women are not able to adapt themselves to this high insulin secretion they could become gestational diabetics. We attempt here to describe the insulin metabolism during late pregnancy according to the women's levels of fasting insulin at six months postpartum. Sixty-seven pregnant women underwent a glucose tolerance test at weeks 20, 30 and 36 of pregnancy and at 6 months postpartum. Glucose and insulin values were measured. The women were classified as follows: group one, women who at 6 months postpartum had fasting insulin levels above the mean (13.5/dl) and group two, who fasting levels were below the mean. The significant difference between the groups was found at all points of the insulin curve at six months postpartum, but not for the glucose curve. During pregnancy, a difference in insulin was also found for weeks 20;30 and 36 but not for the glucose. Group one, whose insulin level were higher since week 20, presented with hyperinsulinaemia, while group two behaved as described in the literature, i.e., secreting more insulin as the pregnancy advanced. Women of group one are at major risk to develop diabetes mellitus, type II later in life (AU)

Evaluation of a screening test for gestational diabetes mellitus

A screening breakfast test was designed and evaluated with good results in non-pregnant women. It was also considered whether to use this screening breakfast test in pregnant women. Forty pregnant women were evaluated between weeks 28 and 32 of gestation; they were diagnosed according to the values of international committees for gestational diabetes. Fourteen of the women were diagnosed as diabetic and 26 were negative. Each woman underwent a tolerance breakfast curve at 0;60;90;120;150 and 180 mins, in order to explore all possible absorption times. Results were analyzed by stratified prognostic test, the optimum time of 60 mins, and postload value of the breakfast test was used to discriminate subjects with and without gestational diabetes. The cut-off point was glucose > 140 mg/dl, with a significance level of p<0.01. A comparison was done of the diagnosis of gestational diabetes, in relation to the screening breakfast test and the glucose test. It was found that the breakfast test had a sensitivity of 92.8 percent; specificity of 96.1 percent and negative prognostic value of 92.8 percent and 96.1 percent, respective; whereas for the glucose test, the results were 100 percent; 76.9 percent; 70.0 percent and 100.0 percent, respectively. The breakfast test can be used as a screening test with similar results to the glucose test (AU)